3 Ton 13 SEER 80% AFUE 100,000 BTU Goodman Gas Furnace and Air Conditioner System - Upflow Review 2026

// Bottom Line

Best for budget-conscious homeowners and contractors seeking a dependable split system without premium efficiency tiers. The two-stage burner and variable-speed blower deliver consistent comfort in moderate climates, though the 80% AFUE rating means higher heating costs than high-efficiency alternatives.

Review

This 3-ton Goodman combo system pairs a furnace and air conditioner in one integrated package, designed for upflow installation in homes up to 1500-1800 square feet. The unit ships as an A-coil configuration, meaning it mounts above a matching air handler or inside a furnace cabinet. Goodman's value-tier positioning focuses on proven components rather than cutting-edge efficiency, making it practical for contractors who prioritize reliability and ease of service over premium features.

Cooling capacity reaches 36,000 BTU through a single-stage reciprocating compressor operating on R410A refrigerant at 13 SEER. That efficiency rating sits comfortably in the baseline tier, delivering respectable seasonal performance without aggressive pricing. Heating generates 100,000 BTU across two burner stages, with 80% AFUE efficiency. The variable-speed blower motor ramps between 0 and 2000 CFM, allowing the system to maintain comfort without constant full-power operation. Electrical requirements remain modest at 120V, 1-phase, 60Hz, needing 19.1 to 30 amp breaker sizing.

Pros & Cons

Pros

Two-stage burner minimizes short-cycling and provides modulating heating output for better comfort
13 SEER cooling efficiency hits the mid-range sweet spot between cost and performance
Variable-speed blower motor adapts airflow up to 2000 CFM, reducing energy waste during partial-load operation
Compact A-coil design fits tight attic or basement spaces with 34.5 inch height
Reciprocating compressor uses R410A refrigerant, proven reliable platform in thousands of installations

Cons

80% AFUE furnace efficiency lags behind 90%+ high-efficiency models, costing $200-400 more annually in natural gas
Single-stage air conditioner compressor cycles on and off rather than modulating, generating higher peak noise at 74 dB
Not Energy Star certified, missing qualification for certain utility rebates and tax incentives
Metal exhaust flue requirement adds installation complexity in retrofit scenarios

Who Should Buy

Best For

Homeowners in mild to moderate climates replacing aging equipment want straightforward reliability without premium pricing. Contractors installing systems for rental properties or cost-sensitive customers benefit from Goodman's field-proven components and straightforward service procedures.

Consider Alternatives If

Skip this if you live in a cold climate where heating dominates utility bills, or if you need Energy Star qualification for rebate programs.

3 Ton 13 SEER 80% AFUE 100,000 BTU Goodman Gas Fur

Buy at HVACDirect →

Installation

Setup requires metal exhaust flue venting and proper refrigerant line sizing with 3/8 inch liquid and 7/8 inch suction lines. The suction line insulation measures 3/8 inch thick and supports up to 30 feet of line length. Sweat-type valve connections demand soldering skills. Mounting dimensions of 34.5 inches tall, 21 inches wide, and 28.75 inches deep fit most attics and utility closets. Ductwork matching 2000 CFM maximum airflow prevents static pressure problems.

Warranty & Reliability

Goodman covers this system with a 10-year parts warranty upon online registration. This standard duration protects against manufacturing defects but excludes labor, refrigerant charging, and consumables. Registration requirement means contractors must complete paperwork before warranty becomes active. No extended options are mentioned, so buyers cannot upgrade coverage beyond the base 10-year term.

Specifications

SKU	LS38783830
Brand/Manufacturer	Online Supply
Cooling BTU	36,000
Heating BTU	100,000
Refrigerant	R410A
Electrical	120 V. 1 Phase 60 Hz
Warranty	10 Years with Online Registration
Decibel Level (dBA)	74
Weight (in lbs)	30.000000
Feature	Spec
Replaces	GSX130362, GSX130363, GSX130365
Energy Star	No
SEER1 (Efficiency)	13
Condenser Stages	Single Stage
Compressor Type	Reciprocating
Liquid Valve Size	3/8"
Suction Valve Size	3/4"
Max Breaker Size	30 amps
Min. Breaker Size	19.1 amps
Tonnage	3.5 Ton
Valve Type	Sweat
Height	34.5"
Width	21"
Depth	28.75"
Resources	Goodman Brochure Goodman Installation Instructions Goodman Parts Manual Goodman Service Manual Goodman Technical Information Goodman User Information Goodman Warranty You will need AdobeÂ® AcrobatÂ® Reader to view PDF documents.
Safety Information	PROPOSITION 65 WARNING This product and many products on our site may contain a chemical know to the state of California to cause cancer or birth defects or other reproductive harm. For more information about Proposition 65 please Click Here.
Configuration	Upflow/Horizontal
Liquid Line	3/8"
Suction Line	7/8"
Style	A-Coil
Airflow Direction	Upflow/Horizontal
Exhaust Flue Requirement	Metal
Furnace Efficiency / AFUE	80%
Blower Motor	Variable Speed
Maximum CFM	2000
Burner Stages	Two
Fuel Type	Propane, Natural Gas
Suction Line Insulation Thickness	3/8"
Length	30 feet

Frequently Asked Questions

How does the 13 SEER rating compare to current market standards? +

13 SEER represents baseline mid-range efficiency. Current market offers 14-16 SEER for modest cost premiums, and 18+ SEER for premium models. SEER1 testing now replaced older SEER measurements, so direct comparisons require updated testing data. For heating-dominant climates, furnace AFUE matters more than cooling SEER.

Can this unit replace my existing furnace and AC separately? +

Yes, but it replaces GSX130362, GSX130363, and GSX130365 condenser models specifically. If your current system differs, verify compatibility with the condenser tonnage and refrigerant type. The 3.5-ton actual capacity must match your home's load calculation, not just your old unit's label.

Why does an 80% AFUE furnace matter for my heating bills? +

80% AFUE means 20% of your fuel energy vents as waste heat. Upgrading to 90-95% AFUE saves roughly 10-15% on annual heating costs. In cold climates, that gap translates to $200-400 yearly. In mild climates heating costs less, so AFUE matters less than SEER.

What's the advantage of the two-stage burner? +

Two-stage operation runs at 60% capacity for mild days and ramps to 100% for cold snaps. This reduces short-cycling, minimizes temperature swings, and improves comfort. Single-stage units fire full power immediately, creating comfort lag and higher peak fuel consumption.

Is the 10-year warranty worth the registration hassle? +

10-year parts coverage is standard at this price tier. Registration is mandatory and takes five minutes online. Warranty excludes labor and refrigerant, so factor service calls into repair budgets. Coverage protects against compressor or heat exchanger failures, the costliest components.

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